Update README.md

README.md

@@ -2,13 +2,64 @@
 
 A higher order reducer for subscribing to `AsyncStream` from your app.
 
+A common pattern in our app for shared data is to create a dependency that exposes an `AsyncStream` of the data that is shared.
+
+Then in the `Reducer` on a `task` action we can do soemthing like...
+
+```
+Reduce { state, action in
+  switch action {
+  case .task:
+    return { send in
+      for await value in await dependency.stream() {
+        await send(.responseAction(value))
+      }
+    }
+  }
+}
+```
+
+When you have a lot of publishers/subscribers this gets very repetetive.
+
+This gives a new way to subscribe to an async stream using a higher order reducer.
+
 Any dependency that returns an `AsyncStream` can be subscribed to in the following way.
 
+# If the action takes the same type as the stream
+
+If the `AsyncStream` `Element` type is the same as the input type of the response action you can just do:
+
 ```
 Reduce {
  // your usual reducer here
 }
-.subscribe(to: myDependency.stream, on: \.some.trigger.action, with: \.some.response.action)
+.subscribe(to: myDependency.stream, on: \.some.trigger.action, with: \.some.response.actionThatTakesStreamElement)
 ``` 
 
-There is a requirement that the AsyncStream returns the same type as the response action takes.
+# If the type doesn't match
+
+If the stream `Element` type needs to be transformed you can do:
+
+```
+Reduce {
+ // your usual reducer here
+}
+.subscribe(to: myDependency.stream, on: \.some.trigger.action, with: \.response.actionThatTakesAString) { streamElement in
+  // return some type created from the streamElement
+  "\(streamElement)"
+}
+```
+
+# If you have a more complex scenarios and want to run some logic
+
+If you don't necessarily need a response action but you want to do something else like running another dependency or something. You can do:
+
+```
+Reduce {
+ // your usual reducer here
+}
+.subscribe(to: myDependency.stream, on: \.some.trigger.action) { send, streamElement in
+  await send(.responseAction)
+  await otherDependency.doSomethingElse()
+}
+```